Watersoluble azodyestuffs



with the addition one nitro-or nitroso group, suchas monoformaldehyde, such Patented Mar. 26, 1935 UN TED- STAT Friedrich Schubert,

Leverkusen-I." G'.

Germany,-assignors to General Aniline Inc., New Yerk, N. ware No Drawing.

Serial No. 643,539. In Germany a 6 Claims.

wherein R stands for hydrogen, an alkylor phenyl radical and Me stands for a monovalent metal radical. V 7

Our new dyestufis are obtainable by starting with any azodyestuii containing at least one nitro group or nitroso group in the molecule and treating the same in aqueous alkaline medium with a mixture of an aliphatic aldehydeor arornatic aldehyde of the benzene series and a watersoluble salt of hyposulfurous acid (152E204) or compound of the aldehyde and a watersoluble salt of "sulfoxylic or hyposulfurous acid. 7 t As starting azodyestuffs therepcome into-consideration any azcdyestuffs containing'at-least distrisand poly-azodyestuffs containing a nitro or nitroso group as substituent and which may bear besides any other substituents. I I As aldehydes there may be mentioned by way of example, formaldehyde or substances yielding as paraldehyde, the homologues of formaldehyde, such as acetaldehyde,

Y., a corporationof Dela-.

. Application new azodyestuff our new process creased solubility in water. new dyestuffs are zoDYEs'rUFFs Heinrich Clingestein, Cologne-on-thc-Bhine, and

Work, Works,

ovember 19, r

November 24,

s" ob are the corresponding starting azodyestuffs.

. In carrying out ournew process as PATENT OFFICE tainable in accordance with distinguished by a highly in The shades of the similarto those obtained with it is surprising that ther'eby are obtained products which still have the constitution of 'azodyestu'ffs. could be expected that the would be split up responding amines by hyposulfurous Hyposulfit and acid (compare azo-brid ge or It rather -bridges withrthe formation of the corthe actionbf sulfoxylic or Anwendung von formaldehyd-sulfoxyl-schwefelsaurem Natrium als fllatzrnittel, Houben, Die

Methoden der'organischen Chemi'e', 2nd 1922, V01. 2, page 354).

Example 19-461 grams edition,

The invention isillustrated bythe' following of the dyestuif which has been prepared by coupling the nitrated diazo compound of lene- 4-sulfonic an aqueous solution of462 g hyde-sodium-sulfoxylate. lution is rendered weakly a the 1-amino-2-hydroxynaphthaacid with e-naphthol, are dissolved with excess caustic soda in: 600 water and stirred for a short time at 50 cos. of C. with rams of formalde- The greenish-blue solkaline by means of aqueous acetic acid, and the dyestuff of the following formula: 1

propionic aldehyde and aldehydes of the benzene V series, such as benzaldehyde, or nuclear substitution products thereof.

In carrying out our new process it is self-understood that there must be worked with at least such a quantity of the aldehyde and sulfoxylate as is sufficient for transforming the nitro or nitroso group into'the group:

Me and R meaning the same as'stated above.

Our new process is carried out in an aqueous allialine reacting agent, such as in aqueous solution or suspension of the azodyestuff, with the addition of an alkali, such as caustic soda, soda is salted out. It dyes which by after-chroming turn Example 2.-572 grams of th wool copper-violet shades to deep black,

e dyestufi which is obtained in accordance with the example of U. S. Patent 1,429,781 by coupling nitro-1-aminobenzene-2-sulfethylanilide amino-S-hydroxynaphthalene-G-sulfonic an acid medium, and some alcohol, and

of one hour at diazotized 4- with 2- acid in a are made into a paste with water introduced in the course G. into a mixture of 700 cos. of water and 200 cos. of alcohol, while simultaneously adding sodium-sulfoxylate and 40 grams of sodium 462 grams of formaldehydedroxide. By means of diluted hydrochloric acid the solution is r dyestuff of the endered weakly alkaline, following formula:

and the S OaNB 5 Nams-cH -HNOrhN V J NH: 7

is salted out by the addition of common salt. In its dry state the dyestuif represents a brown powder, being easily soluble in water.

25 this the solution is rendered weakly alkaline by means of dilute hydrochloric acid The dyestuff f the following formula:

' N=NHO-+COH| NH'OBl-S0:Na NH-on,-:s O Na 40 is completely precipitated by the addition or g The dyestuif is easily soluble'in 50 water, dyes cotton orange shades, can be further diazotiz ed on the fibre and couples with suitable common salt.

coupling components, thereby other shades be ing obtainab We claim:

1. The process which comprises reacting upon an azodyestufi containing a substituent of the tween about 30 and about 8 C. p 1 3. The process which comprises reacting upon an azodyestuff containing a substituent of the various shades. g V v 5. Azodyestufis containing at least once the wherein Me stands for a monovalent metal ra-di-V cal, being soluble in Water, and dyeing fibres various shades. n

6. Azodyestufis of the general formula:

wherein A stands for the radical of an azodyestulf, being soluble in water, and dyeing fibres various shades.

HEINRICH CLINGESTEIN. FRIEDRICH SCHUBERT. 

